The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 02, 2011
Filed:
Jul. 20, 2006
Joseph Purcell, County Clare, IE;
Joseph Purcell, County Clare, IE;
Minroc Technical Promotions Limited, Co. Clare, IE;
Abstract
The invention relates to a drill bit assembly for fluid-operated percussion drill tools comprising a percussion bit () having a head portion () formed with an axially extending stub shank (). The stub shank is provided with axially extending splines (), which are slideably engageable with complementary splines () formed on a drive chuck (). Rotational drive from the chuck () may be transmitted to the stub shank () by means of the splines. Bit retaining means () at the chuck are adapted for engagement with complementary retaining means () at a spline portion of the stub shank to retain the stub shank in the drill bit assembly. Engagement means on the chuck () are adapted for connecting the chuck () to a drive means () of the fluid-operated percussion drill tool. The invention also relates to a down-the-hole hammer comprising an external cylindrical outer wear sleeve (), a sliding piston () mounted for reciprocating movement within the outer wear sleeve () to strike a percussion bit () of a drill bit assembly located at the forward end of the outer wear sleeve () wherein the drill bit assembly is an assembly as described above.